There is a card that pays down your mortgage.

A card that rebates 5 percent of the money you spend on gas.

And a card introduced last year that combines gambling with credit-card use. Each dollar charged to the American DreamCard earns a ticket in a monthly lottery. Spend $1,000, get 1,000 tickets.

The jackpot climbs from $25,000, depending on how many people pay to play.

For consumers, the trend is a chance to pursue rewards of almost any flavor. It's also an enticement to spend more than you had planned.

"If you have a high bill that you can't repay at the end of the month, the whole point of earning a 5 percent reward gets eaten in two seconds by the 18 percent interest rate," said Linda Sherry of Consumer Action, a nonprofit group that tracks the credit-card industry.

Discover kicked off the trend in the mid-1980s with the offer of cash back on every purchase. Then American Airlines paired with Visa to offer a frequent-flier mile for every dollar spent.

Companies have been creating variations ever since. A typical card offers about 1 cent back for every dollar spent, in the form of cash, goods or services.

The goal is simple: "We're hoping to build spending and loyalty," said Mike Sisko, president of American DreamCard.

Success has driven increased competition. In 2001, less than a quarter of credit-card offers included the promise of a rewards program.

Last year, the share was 58 percent, according to Mail Monitor, a unit of consumer-research company Synovate. And at any given moment, some company usually offers rewards worth several pennies on the dollar.

The industry has tried other gimmicks to increase spending and loyalty.

Companies told customers gold cards meant they were special. But as it became clear that many people — some not so special — were getting gold cards, the idea lost its cachet.

Companies continue to aggressively market "affinity cards," which feature the image of something a consumer loves: a sports team, a university, even a picture of the family dog. These cards are popular, but even more so when they are linked with rewards programs.

Studies show that people care more about a card's rewards than about the interest rate, the credit limit or any other feature. "It's the single critical selling point," said Brent Stratford, a vice president at Synovate.

And why not? Most people pay their bills each month. Even consumer advocates who carry long lists of reservations about the industry say rewards programs are a generally positive trend. The programs fall into a few basic categories:

• The classic cash-back rebate. Customers receive a fixed percentage of the money they spend. Variants include programs that give the money to a charity, deposit it in a college savings account, or one that applies the rebate to the customer's mortgage, as does a card offered by mortgage company GMAC.

• The affinity rewards program. The customer chooses a theme, such as fishing or New York City, and accumulates points toward related rewards, which often include such experiences as a fishing trip or reservations at a famous restaurant. Highly popular frequent-flier cards fall into this category.

• The general rewards program. Increasingly, card companies are offering their own rewards, which include a wide range of prizes. For example, many card companies now let customers earn points toward flights on a range of airlines.

The idea of a sweepstakes is not new. Many card companies have conducted prize drawings for their users. But the American DreamCard may be the first card tied to an ongoing lottery.

Sisko said he created the card to extend rewards to lower-income consumers.

"We wanted to give them a meaningful chance at a decent reward," he said.

His company partnered with HSBC Group, one of the largest card issuers. Each month, a drawing is held and a winner announced.

"You know how when there's a large jackpot [in a state lottery] every wants to play?" Sisko asked. "We're hopeful to reach that point some day."

Find a rewards card

Haven't received an offer for the credit card of your dreams?

You can find directories of card options at Bankrate.com and Creditcards.com.

Or surf the Web sites of the largest issuers, including www.bankofamerica.com, www.citibank.com and www.capitalone.com.